The spectrum auction added nearly 4,000 crore rupees of bids on the third day yesterday to take total commitments to almost 61,000 crore rupees. However, over 60 per cent of the airwaves remained unsold as premium 4G bands found no takers.<br/><br/>The debt-ridden telecom players stayed away from high-cost 700 Mhz and 900 Mhz bands. An official source told PTI that bids have come for around 900 Mhz of spectrum at the end of 17th round. The auction will resume today.